(12C Platinum) Cubic Equation

[Thomas Klemm]

Or then use the built-in polynomial solver with this program:

Code:

01-       1    1
02-      34    x<>y
03-      24    ∆%
04-45,43 31    RCL PSE
05-      34    x<>y
06-      33    R↓
07-      25    %
08-      40    +

Examples:

\(x^3 - 4x^2 + 6x - 24 = 0\)

Enter coefficients:

1 CF₀
-4 CF_j
6 CF_j
-24 CF_j

Enter guess:

20 R/S
4.0000

\(-2x^3 + 3x^2 + 4x - 5 = 0\)

Enter coefficients:

-2 CF₀
3 CF_j
4 CF_j
-5 CF_j

Enter guess:

5 R/S
1.8508

Enter guess:

0.5 R/S
1.0000

The advantage is that the same program can be used for higher order polynomials.

Cheers
Thomas

PS: Cf. HP-12C’s Serendipitous Solver